Lack of explanation of intense pain in tooth with root canal

Q.
I had a root canal on tooth #19 about a month ago. I was fine after the procedure. A week later, I went in to get the crown fitting and a post placed. I had intense pain after that was done and 5 days later, I couldn’t feel the left part of my chin and the three teeth next to the one with the root canal felt crowded and tight. I went back to the dentist and he said he had no idea why I was experiencing numbing since they had not done any surgery and therefore, it was unlikely that my nerve had been damaged. He put me on antibiotics and steroids, but it is now it’s now 2 weeks later and the numbness and tightness is still there. The dentist is doing a “wait and see” approach and I am not sure if I should go somewhere else. Could there be more harm in waiting for the numbness to go away? Or is it possible that the nerve just needs time to heal? Please advise me!

A.
Its hard for me to tell without an x-ray but It sounds like an infection that has tracked into the nerve canal, it should resolve but needs checking every few weeks to see if it resolves on its own